1. Field of the Invention
This invention relates to the short milk tube used with milking machines and more particularly to an improvement in the short milk tube.
2. Description of the Prior Art
It is well known that dairymen in the United States lose millions of dollars each year because of mastitis and its concomitant loss of milk production. Although mastitis was known long before milking machines were used, it is still a problem even with modern equipment. Most milk produced at present is drawn from cows by means of a milking machine rather than by hand milking. The machine operates by means of a vacuum created by an appropriately sized pump. A teat cup or metal shell with flexible inside liner or inflation is attached to each teat of the cow's udder and is held in place by vacuum. The reduced pressure inside the teat cup and the massaging action of the flexible liner are responsible for drawing milk from the udder. Milk drawn from each teat by the action of the liner flows through a smooth-bore short milk tube which connects the teat cup and liner with one of the four ferrules or nipples of the claw. The claw is equipped with a single outlet through which milk from the four short milk tubes flows to an appropriate milk collecting reservoir or system. In order to prevent milk from collecting or being held-up in the claw, the bore of the claw outlet is made large enough to handle milk from the four short milk tubes.
During this mechanical milking operation, a combination of factors inherent in the process, including vacuum level, sometimes cause a mixture of air and milk droplets to rush up the short milk tube with sufficient velocity to penetrate the teat sphicter of the cow being milked. Bacteria present in the milk droplets often cause the quarter involved to become infected.
Modifications have been made to prevent such infection. One modification was to increase the bore of the short milk tube. Another was to place a baffle above the opening of the short milk tube to deflect the droplets. However, neither of the modifications proved to be satisfactory. It is not practical to make a tube with a large enough bore to offset the distance the droplets can travel, especially at high velocities. The baffle proved unsatisfactory because it obstructed free drainage of milk from the teat cup and also interfered with cleaning operations. Consequently, a new device or a completely different type of modification was needed to cope with the problem.